The earliest known Pacheco ancestor of New Mexico is Gerónimo Pacheco. He was a Spanish soldier born about 1606 and lived since 1628 (possible earlier) in the San Juan de los Caballeros area near the first Spanish capital (San Gabriel) of New Mexico. San Juan de los Caballeros is located north of modern day Española.

The family of Gerónimo Pacheco was one of the first European families to live permanently in the New World. Gerónimo’s wife, Francisca Cadimo, was the daughter of Francisco Cadimo, a soldier who was one of the 400 colonists who founded New Mexico in 1598 under the leadership of Don Juan de Oñate. New Mexico was first colonized by Don Juan de Oñate, who received a grant in 1595 from the viceroy of New Spain (Mexico) by order of King Philip II of Spain for the "discovery, pacification, and conquest of the provinces of New Mexico". Francisco Cadimo’s father, Pedro Cadimo, was from Salaíces de los Gallegos, Salamanca, Spain.

Juan Pacheco, Gerónimo Pacheco’s son, of the second generation of Pachecos, lived in the same Rio Arriba area of New Mexico as Gerónimo until he, his wife (Antonio de Arratia), three small children, and one servant narrowly escaped massacre during the Pueblo Revolt on August 10, 1680. Juan Pacheco’s daughter, Petrona, was captured by the Indians and thought have been killed. During the revolt, the Indian tribes in New Mexico united and launched a war against the Spanish settlers. Over 400 of the 2900 Spaniards in New Mexico lost their lives. Two-thirds of those killed had been living in the Rio Arriba area. The surviving Spaniards subsequently fled to El Paso.

Several attempts to re-conquer New Mexico failed, until, twelve years later, in August 1692, when Don Diego de Vargas, the governor and captain general of the colony-in-exile, sixty soldiers, and 100 Indians helpers left El Paso and made their way to Santa Fe. They arrived there on September 12, 1692 and were met with mild resistance by the Indians. The Indian occupants surrendered peacefully only after the Spaniards trained their canons on them. Vargas raised the royal banner three times and the Indians repeated after him "Long Live the King." After re-pledging their loyalty to the Spanish crown, the Indians received absolution for their sins. Vargas and his soldiers visited and made peace with all the tribes in the Rio Grande Valley, then with each of the Pueblos to the west. During this "reconquest" Vargas rescued several Spaniards including Juan Pacheco’s daughter Petrona. He made peace without firing a shot until the return to El Paso when they met a band of unfriendly Apaches. Two Apaches died in the ensuing conflict. Once Vargas returned to El Paso, and confident that the reconquest was successful, Vargas planned the resettlement of New Mexico.

On October 4, 1693, Vargas left El Paso with one hundred soldiers, 70 families, eighteen friars and several friendly Indians. Juan Pacheco’s family was among the entourage. Vargas and an advanced party rode ahead and found the Indians had become openly defiant of Spanish rule. Upon returning to the main party, Vargas found more bad news: thirty women and children had died in their trek across the area south of Socorro, since named Jornada del Muerto, meaning Journey of Death. On December 16, they arrived in Santa Fe to find that once again Indians occupied the town. Vargas entered the capital and officially claimed it for Spain. With the completion of the formalities, the Spaniards camped outside Santa Fe and waited for the Indians to leave. This time the Indians refused to leave and the Spaniards settled into a cold, snowy camp outside town. During the two hard weeks that followed, twenty-one colonists died. On December 28 of that year, the Indians dared the Spanish to attack. Two days later they accepted the challenge and captured the town in a typical one-sided battle, made possible by the superiority of Spanish weaponry.

In April 1695, Vargas led forty-four families from Santa Fe into the Española valley and established the villa of Santa Cruz de la Cañada, commonly called La Cañada. Felipe Pacheco, Juan Pacheco’s son and the third generation of Pachecos in New Mexico lived in this valley. He held the military rank of Sargento in 1731. He had one son by his first marriage, to Antonia de Leyva, and six children by his second marriage, to Rosa Martín. A little town north of Española called Los Pachecos is named after the Pacheco family that lived there in the early 1700s, presumably Felipe Pacheco's family. At least five generations of Pachecos after Felipe lived in that area of New Mexico. Not much is known about them other than their names, birthdays, and their wives and children’s names.

New Mexico was under Spanish rule until September 21, 1821, when New Spain (Mexico) formally became an independent country. While New Mexicans had taken no direct part in the revolution with Spain, they welcomed the news. They envisioned an end to the prohibition on trade with outsiders. With the demise of Spanish rule, Mexican officials removed the restrictions on commerce.

The great separation in time and distance between New Mexico and Mexico City resulted in loose control of affairs in New Mexico by the central Mexican government. It also meant that Catholic Church officials in Mexico failed to support the church in New Mexico, essentially leaving the northern church leaders on their own. As a result, many New Mexicans did not really think of themselves as Mexicans. Left alone by state and church officials, New Mexicans developed no deep sense of loyalty towards Mexico.

Texas had claimed independence from Mexico after the battle at San Jacinto in 1836. The famous battle cry used by the Texans in this battle was "Remember the Alamo", referring to battle at the San Antonio mission where 187 Texan defenders were killed by a Mexican force of 4000. During the expansionist campaign of the United States run by the newly elected president James Polk, the United States tried and failed to purchase California from Mexico for $25 million. Just prior to Polk being sworn into office, the U.S. Congress annexed Texas in March 1945. Mexico had never official recognized Texas's independence and complicated the issue by claiming the southern border of Texas was no further south then the Nueces River, where as the United State claimed the southern border to be the Rio Grande. Polk forced the issue in March 1846 by ordering General Zachary Taylor to cross the Nueces River and go all the way to the Rio Grande. Mexican General Pedro Ampudia sent a message to Taylor asking him to move his troops back across the Nueces River or face war with Mexico. When Taylor did not move his troops, the Mexican army crossed the Rio Grande and soundly defeated Taylor’s party. This gave Polk the perfect excuse to declare war against Mexico which Congress voted for on May 13, 1846. The army campaigned in small numbers and had to march across vast areas to accomplish their objectives.

U.S. Army commander Stephen Kearny sent a message to the governor of New Mexico, Manual Armijo, urging him to surrender. Kearny’s representatives met privately with him and may have paid him several thousand dollars for his cooperation. Kearny led a small number of soldiers (about 1500) to Las Vegas claiming New Mexico for the United States, promising the people they had nothing to fear. Kearny moved towards Santa Fe and when he arrived, Armijo had already left to Albuquerque. Kearny’s conquest of New Mexico was a bloodless affair.

The U.S. armies prevailed, occupying California and winning important victories in northern Mexico. Both sides signed a treaty on February 2, 1848 and California and the territory of New Mexico became parts of the United States.

Some time after the Mexican-American war, between 1860 and 1888, Abundio Pacheco, Felipe’s great-great-great grandson, and his brothers moved from the San Juan area to a little hamlet near Mora called Pacheco Village. This village was named after the Pachecos who lived there. Many of their descendants still live there today. Other Pacheco descendants now live elsewhere in New Mexico, yet others have moved all over the United States and the world.